<template>
	<div :class="{'show':show}" class="header-search flex-start-center">
		<div class="search-icon el-icon-search" @click.stop="click" />
		<el-select
			ref="headerSearchSelect"
			v-model="search"
			:remote-method="querySearch"
			filterable
			default-first-option
			remote
			placeholder="Search"
			class="header-search-select"
			@change="change"
		>
			<el-option v-for="option in options" :key="option.item.path" :value="option.item" :label="option.item.title.join(' > ')" />
		</el-select>
	</div>
</template>

<script>
// fuse is a lightweight fuzzy-search module
// make search results more in line with expectations
    import Fuse from 'fuse.js/dist/fuse.min.js';
    import path from 'path';

    export default {
        name: 'HeaderSearch',
        data() {
            return {
                search: '',
                options: [],
                searchPool: [],
                show: false,
                fuse: undefined
            };
        },
        computed: {
            routes() {
                return this.$store.getters.permission_routes;
            }
        },
        watch: {
            routes() {
                this.searchPool = this.generateRoutes(this.routes);
            },
            searchPool(list) {
                this.initFuse(list);
            },
            show(value) {
                if (value) {
                    document.body.addEventListener('click', this.close);
                } else {
                    document.body.removeEventListener('click', this.close);
                }
            }
        },
        mounted() {
            this.searchPool = this.generateRoutes(this.routes);
        },
        methods: {
            click() {
                this.show = !this.show;
                if (this.show) {
                    this.$refs.headerSearchSelect && this.$refs.headerSearchSelect.focus();
                }
            },
            close() {
                this.$refs.headerSearchSelect && this.$refs.headerSearchSelect.blur();
                this.options = [];
                this.show = false;
            },
            change(val) {
                if (this.ishttp(val.path)) {
                    // http(s):// 路径新窗口打开
                    window.open(val.path, '_blank');
                } else {
                    this.$router.push(val.path);
                }
                this.search = '';
                this.options = [];
                this.$nextTick(() => {
                    this.show = false;
                });
            },
            initFuse(list) {
                this.fuse = new Fuse(list, {
                    shouldSort: true,
                    threshold: 0.4,
                    location: 0,
                    distance: 100,
                    maxPatternLength: 32,
                    minMatchCharLength: 1,
                    keys: [{
                        name: 'title',
                        weight: 0.7
                    }, {
                        name: 'path',
                        weight: 0.3
                    }]
                });
            },
            // Filter out the routes that can be displayed in the sidebar
            // And generate the internationalized title
            generateRoutes(routes, basePath = '/', prefixTitle = []) {
                let res = [];

                for (const router of routes) {
                    // skip hidden router
                    if (router.hidden) { continue; }

                    const data = {
                        path: !this.ishttp(router.path) ? path.resolve(basePath, router.path) : router.path,
                        title: [...prefixTitle]
                    };

                    if (router.meta && router.meta.title) {
                        data.title = [...data.title, router.meta.title];

                        if (router.redirect !== 'noRedirect') {
                            // only push the routes with title
                            // special case: need to exclude parent router without redirect
                            res.push(data);
                        }
                    }

                    // recursive child routes
                    if (router.children) {
                        const tempRoutes = this.generateRoutes(router.children, data.path, data.title);
                        if (tempRoutes.length >= 1) {
                            res = [...res, ...tempRoutes];
                        }
                    }
                }
                return res;
            },
            querySearch(query) {
                if (query !== '') {
                    this.options = this.fuse.search(query);
                } else {
                    this.options = [];
                }
            },
            ishttp(url) {
                return url.indexOf('http://') !== -1 || url.indexOf('https://') !== -1;
            }
        }
    };
</script>

<style lang="scss" scoped>
.header-search {
  font-size: 0 !important;

  .search-icon {
    cursor: pointer;
    font-size: 18px;
  }

  .header-search-select {
    font-size: 18px;
    transition: width 0.2s;
    width: 0;
    overflow: hidden;
    background: transparent;
    border-radius: 0;
    display: inline-block;
    vertical-align: middle;

    ::v-deep .el-input__inner {
      border-radius: 0;
      border: 0;
      padding-left: 0;
      padding-right: 0;
      box-shadow: none !important;
      border-bottom: 1px solid #d9d9d9;
      vertical-align: middle;
    }
  }

  &.show {
    .header-search-select {
      width: 210px;
      margin-left: 10px;
    }
  }
}
</style>
